A construction project’s planning, design, and construction can be organized in several ways, also known as delivery methods. Like contract types, delivery methods dictate the contractual relationships between the client and the contractor, while adding the design consultant to the equation. Delivery methods also affect construction project phases, and the tasks they entail. Certain construction project delivery methods work better for some projects than others. The four common ones are Design-Bid-Build (DBB), Design-Build (DB), Construction Manager at-Risk (CMR), and Multi-Prime (MP).
Design-bid-build
This traditional construction project delivery method is very linear, with three separate phases: design, bidding, and construction.
The owner signs two separate contracts, one with the architect (and any other engineers and design professionals), and another with the building contractor. The architect is responsible for providing the details of the design, and is thus liable for any gaps between the owner’s intentions and the contract documents. In turn, the contractor is responsible for building the project in accordance with the approved drawings and specifications, for the price they quoted during bidding.
When is this method right for your project?
If you prefer a well-known and widely accepted method that lets you work directly with a designer, DBB may be a good choice for you. Just keep in mind that you will have to do your part and collaborate with the design team on an ongoing basis.
On the downside, precious field experience may be absent from the design process, given the contractor’s late involvement in the project. This lack of hands-on construction knowledge during design can reduce the project’s constructability and expose you to contractor-initiated change orders. To ensure a successful outcome, you should find alternative means of getting construction input during the design phase, which is often accomplished by retaining a general contractor early in design for preconstruction services. For complex projects, a skilled construction manager is essential in determining the right project delivery method
Design-build
A more collaborative approach, the DB method entails a consortium between the designer and the builder. The architect, engineer, and general contractor function as one entity throughout all construction project phases, yet either may be chosen to lead the consortium.
Typically, the owner enters into one contract with the design-builder, and another with their “bridging consultant” – an architect responsible for the illustrative drawings and output specifications that comprise the owner’s design requirements and performance criteria, called the Basis of Design. The owner establishes these non-prescriptive standards, and the design-builder uses them as a basis of their drawings and specifications, and ultimately, the building itself. The design-build consortium is responsible for identifying discrepancies between owner’s performance requirements and their design, while the owner must cover the costs of closing the gap.
When is this method right for your project?
The DB method tends to deliver projects quickly. Thanks to the early coordination between contractor and designer, which continues throughout the design phase, design flaws and the resulting change orders can be averted with greater ease. However this approach requires a sophisticated owner that knows exactly what they want, who is unlikely to make changes during construction. The importance of the Basis of Design document to contractually set expectations cannot be underestimated. With complex projects the risk of cost overruns becomes higher in design build, as one entity is managing both and the owner may not have sufficient leverage to enforce the contract price.
If you have a very clear and straightforward program, prioritize time and wish to minimize changes, you may find that the DB method is well-tailored to your needs. Likewise, if you wish to know the building’s projected costs early on, the DB method may suit you well, as the contractor’s involvement allows accurate cost estimates at various stages of design.
Conversely, if you prefer a stronger hand in managing the design, you may be unsatisfied with the lack of control over the design process, and the fact that the project architect-of-record works for the contractor and not for you.
Construction Management at Risk
Similar to the traditional DBB model, the CMR method is linear in terms of process and contractual obligations. There are two separate contracts, one between owner and CM constructor, and one between owner and architect/designer. Similar to DBB, the owner is responsible for providing prescriptive design requirements and reconciling these with the drawings and specifications.
A major difference (and advantage) of the CMR method is the contractor’s early participation in design. Field experience brings immense value to the project, as many design flaws can be averted with the contractor’s advice. As well, projects delivered with this method may progress faster than those using DBB. Alternately, a general contractor may be retained for preconstruction services, which is similar to this CMR method.
As with DBB, the lack of a contractual relationship between the designer and the builder can lead to disagreements about the quality and completeness of work, hostile relationships, claims, and litigation.
When is this method right for your project?
The CMR method is best suited for owners who favor a direct relationship with the designer, and the level of control it gives over the design. It’s also a good choice if you prefer to know the expected costs sooner, and possibly adjust the design based on these projections. Finally, the method is well-suited for complex projects, where a builder’s perspective can enhance the design’s constructability.
Multi-Prime
In the multi-prime (MP) delivery method, the duties of GC are performed by the owner, who signs separate contracts with the architect, possibly a general contractor, and numerous trade subcontractors. This gives the owner a firm grip over the project, as they end up managing trades that would normally report to the GC. Thanks to the high level of oversight the MP method allows, it is common on public sector projects. However, the owner must be very sophisticated or employ a skilled construction manager to manage so many independent contracts.If you have substantial experience managing construction activities, the MP method can afford you a great degree of control of the project. On the other hand, you must be ready to manage each subcontractor separately and prepare for the possible challenges in estimating costs and coordinating the schedule. In this case, the owner, and not the trade contractors, is responsible for gaps in scope between trade packages
.
An appropriate delivery method can help you achieve some key objectives. Factors such as control over design, control over construction, efficiency, and prompt delivery are all dependent on the method you select.
That said, the right construction project delivery method is not enough to avert all problems from your site. Unforeseen conditions, change orders and deficiencies will still emerge from time to time. Retaining a professional construction manager will help you determine the best method for your project and to oversee the project for success
